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We investigate the effects on cosmological density perturbations of dark radiation in a Randall-Sundrum 2 type brane-world. Dark radiation in the background is limited by observational constraints to be a small fraction of the radiation…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Burin Gumjudpai , Roy Maartens , Christopher Gordon

Recent measurements of cosmological parameters from the microwave background radiation, type Ia supernovae, and the age of globular clusters help determine the relic matter density in the universe. It is first shown with mild cosmological…

High Energy Physics - Phenomenology · Physics 2009-10-31 James D. Wells

We investigate the question of how tightly we can constrain the cosmological parameters by using the ``cosmic inversion'' method in which we directly reconstruct the power spectrum of primordial curvature perturbations, $P(k)$, from the…

Astrophysics · Physics 2009-10-09 Noriyuki Kogo , Misao Sasaki , Jun'ichi Yokoyama

We constrain interacting dark matter and dark energy (IDMDE) models using a 450-degree-square cosmic shear data from the Kilo Degree Survey (KiDS) and the angular power spectra from Planck's latest cosmic microwave background measurements.…

Cosmology and Nongalactic Astrophysics · Physics 2018-02-27 Rui An , Chang Feng , Bin Wang

Once dark matter has been discovered and its particle physics properties have been determined, a crucial question rises concerning how it was produced in the early Universe. If its thermally averaged annihilation cross section is in the…

High Energy Physics - Phenomenology · Physics 2019-11-06 Paola Arias , Nicolás Bernal , Alan Herrera , Carlos Maldonado

We analyze observational signatures arising from an epoch in cosmology corresponding to the simple harmonic universe, which consists of positive curvature, a negative cosmological constant, and one or more exotic matter sources with $-1 < w…

Cosmology and Nongalactic Astrophysics · Physics 2019-12-19 Peter Gilmartin , Bart Horn

Updated constraints on dark matter cross section and mass are presented combining CMB power spectrum measurements from Planck, WMAP9, ACT, and SPT as well as several low-redshift datasets (BAO, HST, supernovae). For the CMB datasets, we…

Cosmology and Nongalactic Astrophysics · Physics 2014-12-01 Mathew S. Madhavacheril , Neelima Sehgal , Tracy R. Slatyer

We quantify the accuracy with which the cosmological parameters characterizing the energy density of matter (\Omega_m), the amplitude of the power spectrum of matter fluctuations (\sigma_8), the energy density of neutrinos (\Omega_{\nu})…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Surhud More , Frank van den Bosch , Marcello Cacciato , Anupreeta More , Houjun Mo , Xiaohu Yang

We discuss an alternative approach to quintessence modifying the usual equation of state of the cosmological fluid in order to see if going further than the approximation of perfect fluid allows to better reproduce the available data. We…

Astrophysics · Physics 2008-11-26 S. Capozziello , V. F. Cardone , S. Carloni , S. De Martino , M. Falanga , A. Troisi , M. Bruni

We use the Allen et al. (2008) galaxy cluster gas mass fraction versus redshift data to constrain parameters of three different dark energy models: a cosmological constant dominated one ($\Lambda$CDM); the XCDM parameterization of dark…

Astrophysics · Physics 2010-11-11 Lado Samushia , Bharat Ratra

We study the possibility to explain the non-baryonic dark matter abundance and improve the present fits on the muon anomalous magnetic moment through the same new physics. The only viable way to solve simultaneously both problems which is…

High Energy Physics - Phenomenology · Physics 2008-11-26 J. A. R. Cembranos , A. Dobado , A. L. Maroto

In these Lectures I review possible constraints on particle physics models, obtained by means of combining the results of collider measurements with astrophysical data. I emphasize the theoretical-model dependence of these results. I…

High Energy Physics - Phenomenology · Physics 2017-08-23 Nikolaos E. Mavromatos

When combining cosmological and oscillations results to constrain the neutrino sector, the question of the propagation of systematic uncertainties is often raised. We address this issue in the context of the derivation of an upper bound on…

Cosmology and Nongalactic Astrophysics · Physics 2017-10-25 F. Couchot , S. Henrot-Versillé , O. Perdereau , S. Plaszczynski , B. Rouillé d'Orfeuil , M. Spinelli , M. Tristram

We derive constraints on a coupled quintessence model with pure momentum exchange from the public $\sim$1000 deg$^2$ cosmic shear measurements from the Kilo-Degree Survey and the $\it{Planck}$ 2018 Cosmic Microwave Background data. We…

Cosmology and Nongalactic Astrophysics · Physics 2022-03-16 A. Spurio Mancini , A. Pourtsidou

We study the $S3$ symmetric extension of the Standard Model in which all the irreducible representations of the permutation group are occupied by $SU(2)$ scalar doublets, one of which is taken as inert and can lead to dark matter…

High Energy Physics - Phenomenology · Physics 2018-11-21 C. Espinoza , E. A. Garcés , M. Mondragón , H. Reyes-González

We investigate aspects of cosmology in brane world theories with a bulk scalar field. We concentrate on a recent model motivated from supergravity in singular spaces. After discussing the background evolution of such a brane-world, we…

High Energy Physics - Theory · Physics 2014-11-18 P. Brax , C. van de Bruck , A. C. Davis

Extra-dimensional theories contain additional degrees of freedom related to the geometry of the extra space which can be interpreted as new particles. Such theories allow to reformulate most of the fundamental problems of physics from a…

High Energy Physics - Phenomenology · Physics 2008-11-26 J. A. R. Cembranos , A. Dobado , A. L. Maroto

After reviewing the main mechanisms by which cosmological measurements constrain the sum of neutrino masses, I give the current reached upper limits, emphasizing the level of model-dependence. A large improvement is to be expected with…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 Stephane Plaszczynski

In unparticle dark matter (unmatter) models the equation of state of the unmatter is given by $p=\rho/(2d_U+1)$, where $d_U$ is the scaling factor. Unmatter with such equations of state would have a significant impact on the expansion…

Astrophysics · Physics 2008-12-18 Yan Gong , Xuelei Chen

The current expansion of the Universe has been observed to be accelerating, and the widely accepted spatially-flat concordance model of general relativistic cosmology attributes this phenomenon to a constant dark energy, a cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2023-04-13 Shulei Cao